Components of the aforesaid kind are known, for example, from the document WO 99/07023. In these components, an optoelectronic chip is fixed on a chip carrier. The chip and portions of the chip carrier are surrounded by and embedded in a housing. The housing can be fabricated by injection overmolding. The chip carrier has a region on which the optoelectronic chip is fixed. The chip carrier also has terminals that run from the chip-carrying region outwardly out of the housing. There, the terminals generally form soldering surfaces by means of which the component can be soldered fast to a board.
Components of the aforesaid kind are being used increasingly as preferred light sources, for example in the form of light-emitting diodes, in industry, automotive technology, telecommunications and other areas. Requirements as to the mechanical stress behavior and reliability of the components are also increasing sharply as a result. Mechanical requirements relating to thermomechanical stress behavior are especially high.
The reliability of such a component can be quantified by means of a characteristic number whose unit is parts per million (ppm). This measures how many components out of a million show evidence of failure. Current demand is for failure rates of close to 0 ppm.
The known components of the aforesaid kind have the disadvantage that from the standpoint of reliability, they are unable to attain the desired failure rate. A characteristic weakness is that too often the connection between the optoelectronic chip and the chip carrier becomes damaged or splits apart. This can be caused by the fact that when the component is subjected to thermal stresses, of the kind that can occur for example as the terminals are being soldered to a board, the disparate thermomechanical properties of the materials used come to the fore and cause stress. For example, it is customary to use materials having very different thermal expansion coefficients to fabricate the components. The materials—for example, those of the chip carrier and the housing—also differ with respect to their modulus of elasticity. Because of these differences in the materials, strong mechanical forces arise under thermal stress that can deform the individual constituents of the materials or cause them to slide or shear relative to one another.